Seize the means of production. Of society, which produces man. Man is the consequence of his social circumstances.
Society produces man but, by using the state as a an intermediary of power, man produces society. And, then, the society produces man.
Man is the creator taking society and his species as his own objects. Man creates society, creates man, creates society.. in an endless dialectical loop until man an dsociety have no distance between them any longer and they are perfectly realized as socialist man in socialist society. Perfected man made to live in perfected society.
This is the theology of Marxism:
What, though, is this dialectical materialism? Is it just a theory of man and society?
No, i tactually answers fundamental questions of life and man's role in it. Not only man's role in it, that man has to seize the means of control of production of society so he can control man (that's eugenics - control the production of man - it doesn't have to be direct biological eugenics, but it's still eugenics - changing man fundamentally to be something different with a targeted endpoint).
From Engels, in the Dialectics of Nature (fundamental theory of everything), he describes what got called "Dialectical Materialist" this way:
"It is an eternal cycle in which matter moves. A cycle that certainly only completes its orbit in periods of time for which our terrestrial year is no adequate measure. A cycle in which the time of highest development, the time of organic life, and still more, that of the life of the being conscious of nature and of themselves is just as narrowly restricted as the space in which life and self-consciousness come into operation. The cycle in which every finite mode of existence of matter, whether it be sun or nebular vapour, single animal or genus of animals, chemical combination or dissociation as equally transient and wherein nothing is eternal but eternally changing, eternally moving matter and the laws according to which it moves and changes.
*So it's not just man and his economic materialism that Marx focused on that's transforming us dialectically. Literally everything in the universe is transforming itself dialectically. This is a theory of the entire operation of Universe and man and man's role in it with specific duties given to man for what to do - be the one who figures out the way that it moves (by claiming power through the state and pushing it along, consciously, towards a directed outcome of Socialism).
This is a religion. This is a total explanation for the fundamental questions of life in the world, man's role in them that gives rise to duties of conscience, and it is obviously a comprehensive set of thought belief and practices (Activism).
So now we know Marx's ontology of man - the theory of what it means to be man: Man has no other creator but himself.
But in Marx and his acolytes after him, a lot of time was focused on this existential scream of Marxism: Man is not mere animal.
Animals engage in activity - not work. They don't transform the world. They conform themselves to the world. Animals are subject to the sovereignty of the order of the universe (logos). Man is, actually, free from that. He is different.
Man has the ability to engage in conscious awareness as he engages in his work to transform the world. The most key thing that changes the world or transforms the world or produces value or means anything that makes man who man is and what man should realize through his work - is that he is able to picture what he brings into creation before he does it, whereas animals just act by extinct.
"A spider conducts operations that resemble those of a weaver, and a bee puts to shame many an architect in the construction of her cells, but what distinguishes the worst architect before the best of the bees is this: that the architect raises his structure in imagination before he erects it in reality."
So, you picture what you want to see and then you make it. This creates a dialectical/ontological process by which man can come to know who he is.
Man pictures the world he wants to make and then makes it - that makes him a creator. This is how Marx resolves that Subject - Object dialectic that Hegel also talked about:
He has the capacity to transform dead matter from nature to something functional for man. I have humanized the thing suited for use by man. I create the conditions in which I love, and the goal of the Subject-Object dialectic is for man to realize that he is in this relationship - he is a subject who can create the world he wants to live in.
Unlike the animals, which conform to the world that they're in, Marxists transform the world to become what they want it to be. But it's not just matter that you transform. Man takes himself and his species as his own object. Man takes society as his own object.
Man is a being who can envision what he wants so he can conform the world through his work to himself. He is above the mundane and capable of transforming/humanizing the world. He makes matter and people into things that do that which is more suitable to the human. Humanize the world and the society and the species and, in the process, he is returning everything to its true nature, which is Social.
From the Economic and Philosophic Manuscripts: "But man is not merely a natural being, he is a human natural being. That is to say, he is a being for himself. Therefore he is a species-being, and has to confirm and manifest himself as such in both his being and his knowing. Therefore, human objects are not natural objects, as they are immediately present themselves, but neither is Human Sense as it immediately, as it is objectively Human Sensibility - Human Objectivity. Neither nature nor nature subjectively is directly given in a form adequate to the Human Being."
Man has to make nature, the world, everything that he takes as his object, into something suitable for him. Something good enough for him.
You train the ear and the eye to become human. Not a crude eye or crude ear, like an animal. Man is a creature that has the capacity to transform himself and lift himself beyond the mere animal. We won't quite say, to God, because Marx exemped himself from God, but he is talking about transforming what it means to be a man, and the world, so that it is all given into a form adequate to a Human Being. The world has to be transformed to make it Human. Turn the Jungle into a Garden - you have humanized it. Look at raw nature and look at the messy, ugly city, and figure out how to make nature more like the city and the city more like nature. Work is how this is done. The Liturgy o fthe Marxist Theology is work, or The Work
The goal of being human is to realize that you're a species being. A being that operates in the context of being for the whole species - a collectivist.